Production of 1-acylaminoethyl-phosphinic acid derivatives

摘要

Preparation of 1-acylaminoethylphosphinic acid derivatives of formula R<4>CH2C*H(NHR<3>)P(=O)(R<1>)OR<2> (I) comprises hydrogenating a 1-acylaminovinylphosphinic acid derivative of formula CH(R<4>)=C(NHR<3>)P(=O)(R<1>)OR<2> (II) in the presence of a catalyst comprising a chiral or achiral rhodium complex of formula (III) or a rhodium complex of formula (IV): R<1> = 1-4C alkyl or 2-5C alkoxyalkyl optionally substituted by N, O, P, S or halo, or aryl, aralkyl, heteroaryl or cycloalkyl optionally substituted by N, O, P, S, halo, 1-4C alkyl, 1-4C alkoxy or 2-5C alkoxyalkyl; R<2> = H, alkali metal, ammonium or as for R<1>; R<3> = acyl, e.g. acetyl, trifluoroacetyl, benzoyl, benzyloxycarbonyl, t-butoxycarbonyl, methoxycarbonyl or ethoxycarbonyl; R<4> = aryl or heteroaryl optionally substituted as above; X = alpha -naphthyloxyalkyl; Y = H; Z = n-alkyl, isoalkyl or cycloalkyl; R = a protecting group corresponding to R<3>.